PERMFILE138525

• Permit No: M2006018
• IBM Index Class Name: PERMIT FILE
• Doc Date: 5/25/2006
• Doc Name: 2nd Adequacy Review Comments
• From: DMG tas
• To: LaFarge West Inc
• Media Type: D
• Archive: No

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STATE OF COLORADQ
I ~ DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
FA%; [phone]
May 25, 2006
Mr. Mazk Vigil
Lafarge West, Inc.
10170 Church Ranch Way, Ste. 200
Westminster, CO 80021
COLORADO
DIVISION O E
M[NSRALS
GEOLOGY
RFCIANATION•NINING
SAfETT•SCIENCF
Bill Owens
Governor
Russell George
Executive Director
Ronald W. ranany
Division Director
Natural Resource Trustee
RE: 2"d Adequacy 12eyier~Cnmments•-North $ank Pit, Regular 112 Application
Class: Permit, File No. M-2006-018
Dear Mr. Vigil:
The Division has now completed its review of your May 19, 2006 adequacy response. Listed
below aze remaining adequacy review comments on the above-captioned Regulaz 112 application
for 237.67 acres located 2.2 miles east of Rifle. Please respond by no later than 4:00 P.M. today
(May 25, 2006) in writing whether you prefer to waive your right to a decision within 90 days
and request an extension of the decision date to allow sufficient time to resolve the remaining
concerns. Please note that the application is not adequate at this time for approval. As an
alternative, you may also withdraw the application at this time and re-submit at a later date with
the requested information.
6.4.4 EXHIBIT D - Mining Plan
3. The applicant specifies that pit water from de-watering operations will be discharged
according to an approved plan into existing sloughs in order to return the water to the Colorado
River system. (Exhibit C -Mine Plan Map shows a total of 4 locations for conveyance of pit
water to the Colorado River. It appeazs there will need to be a conduit or water transfer system
of almost two hundred (200) feet for each point of water conveyance). In conformance with Rule
6.4.7(2) (c), please describe and provide representative cross sectional diagrams of how the pit
water will be managed, routed, and dischazged into the Colorado River sloughs in a manner that
protects against pollution of either surface or groundwater resources and minimizes the potential
for erosion of the affected land. Also, the applicant will need to quantify the maximum velocity
and rate of water discharged at each point of dischazge. (The applicant has estimated a de-
watering rate of 250 to 750 gpm}. Please respond.
4a. The applicant has proposed a 100-foot setback from the Colorado River to the nearest point
of pit excavation in order to ensure that during high-water events, the river does not capture the
Office of Office of Colorado
Mined Land Reclamation Active and Inattive Mines Geological Survey